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Research indicates that grain size and concentration of abrasive material should be reasonably selected based on the surface roughness.
And Inhomogeneity of concentration distribution along wheel circumference will result in heterogeneity of insulator layer state, which will bring difference in the number of abrasive grain in the grinding area, thereby changing the actual cutting depth of every abrasive grain.
Selection of grain size and abrasive material concentration It is known well enough that grain size and concentration of abrasive material should be choiced rightly based on the surface roughness and maching efficiency.
Inhomogeneity distribution of various components on the surface of abrasive tool will result in heterogeneity of insulator layer state, which will bring difference in the number of abrasive grain in the grinding area, thereby changing the actual cutting depth of every abrasive grain.
Main conclusions of this paper are as follow: 1) Abrasive grain size and diamond wheel concentration should be reasonably selected based on the demand of surface roughness, and each grinding depth and feed frequency in vertical direction of maching surface should always be scientifically determined. 2) Inhomogeneity of concentration distribution along wheel circumference will result in difference in the number of abrasive grain, thereby change the actual cutting depth of every abrasive grain.

Grain refiners are widely used in the foundry.
They are considered to provide benefits in a number of ways including improved feeding during solidification, reduced and more evenly distributed porosity, and reduced hot tearing [5].
Grain refiner is added to make smaller, more uniform, equiaxed grains.
To produce cast ingots with fine grain size, grain refiners are added.
Affects the mechanical properties of the material the smaller the grain size, more are the grain boundaries.

Because of the high vibration frequency of the system, the sample surface was peened repetitively by a large number of balls within a short period of time.
With successive grain subdivision, the grain refinement continues and hence, the ultrafine and nc grains are formed, as shown in Fig. 3(a) and (b) at ~ 70 and 25 µm deep, respectively.
Fig. 5(a) shows a grain of ~ 80 nm in size.
The grain refinement stems from grain subdivision due to {1010 }〈1120 〉 prism and {0001}〈1120 〉 basal slip.
The grain refinement of ε-cobalt is realized through grain subdivision by the {1010 }〈1120 〉 prism and {0001}〈1120 〉 basal slip.

In this case only these specific, slowly etched grains will have interference color, as the thickness of the interfering layer above all the other grains will pass the transparency borderline.
It is also interesting to note, that the surface of the higher grains – which are close to the (111) orientation – are smooth, while all the other grains have striped patterns.
To selectively filter the grains which are close to the (111) direction several established grain detection algorithms – such as the watershed, for example – could be used [12].
Conclusions A method to identify and quantify the number of grains which are close to the (111) orientation in a cold rolled steel sample was presented.
An effective image processing method for the identification of the grains based on the latter property was proposed and demonstrated for blue (111) grains.

Potential Measurement of Grain Boundary and Grain Interior.
Potentials of the grain boundary and the grain interior are shown in Fig. 2.
Precipitation State on Grain Boundary and Grain Interior.
Also, there were a number of Al15Mn3Si2 precipitates in the grain interior.
Hence, potential differences between the grain boundary and grain interior became large and IGC easily occurred.

However, practical application of such materials requires solving a number of materials science problems such as the decrease of ordered phase formation temperature, formation of its predominantly oriented grains and the increase of coercivity.
A number of modern studies aimed on solving problems mentioned above have been analyzed.
A large number of studies are aimed on solving these problems.
Grain boundary diffusion of Ag may facilitate the increase of coercivity of films due to the decrease of magnetic interaction in between grains of L10-FePt phase (grains magnetic isolation).
Summary We have examined a number of modern works that discuss the ways of L10-FePt ordered phase formation temperature decrease, formation of predominant orientation of its grains and enhancement of its coercivity.

In the process of describing a grinding wheel, the grit number is related to the mesh number of the screens used to sort the grains.
(Table 1) Clearly, when counting the static grain density, there is a theoretical upper bound to their number.
For a given grit number, they were expressed as gavgdµ= (3) ( )/3 gmax gavgd d σ= − (4) To generate the wheel topography, the grinding wheel is mesh with a grain interval.
The grain interval is the distance between two adjacent grains.
And the effective grains number is quite useful in predicting the finished workpiece surface.

In order to enhance the material’s strength, refining the prior austenite grain size through repeated-heating was investigated in our previous work.
In the case of high-carbon high-chromium steels, refining the prior austenite grain size improves the material strength.
In the modified S-N diagram, the relation between stress amplitudes at the crack origin depths and the numbers of cycles to failure is shown.
The grain sizes of Q1T1 and Q3T1were approximately 15 mm and 7 mm, respectively.　
Prior austenite grain size of Q2T1 sample in the present observation is less than that of Q1T1 sample.

The influence of alloying elements on grain boundary and bulk cohesion in aluminum alloys: ab initio study.
There exist a number of ab initio studies of the impurity effect on the GB’s energy characteristics in aluminum [11,12,13], where the special GB was studied and the effect of Ga and Ca on the set of GB’s properties was estimated.
Rybin: Grain boundaries in metals (Metallurgy, Moscow, 1980)
Straumal: Grain boundaries phase transitions (Nauka , Moscow, 2003)
Shvindlerman: Thermodynamics and Kinetics of Grain Boundaries in Metals (Metallurgy , Moscow, 1986)

�Grain boundary carbides-related parameters, such as number or area fraction, were sometimes reported to have favorable correlations with thermal degradation [5].
In this work, AGBC was defined as the total area of grain boundary carbides divided by grain boundary length examined.
FGBM6C was defined as the number of grain boundary M6C carbide (i.e., Fe>Mo>Cr) divided by number of total grain boundary carbides analyzed.
The different characteristic of grain boundary carbides with those of carbides inside grains needs to be independently monitored for assessment of thermal degradation.
� ������� � 0 10 20 30 40 50 60 0.08 0.10 0.12 0.14 0.16 0.18 480 500 520 540 560 580 600 620 640 660 Fraction of GB M6C Carbide (R=0.89) Fraction of GB M6C Carbides [%] UTS [MPa] Total Area of GB Carbides (R=0.74) Total Area of GB Carbides/GB Length [µµµµm] 0.08 0.10 0.12 0.14 0.16 0.18 80 84 88 92 96 100 Rockwell Hardness [HRB] Mean Size of Carbides [µµµµm] Globular (M6C) Carbides (R=0.95) All Carbides (R=0.83) 0 1000 2000 3000 4000 5000 0 10 20 30 40 50 60 Theraml Degradation Time [hour] Number of M6C carbides x100 Number of grain boundary carbides analyzed Fraction of M6C Carbides at Grain Boundary [%] Kinetic Energy [eV] Intensity [arbitrary] (a) (b) Fe Fe C Cr Mo C Mo Kinetic Energy [eV] Intensity [arbitrary] (a) (b) Fe Fe C Cr Mo C Mo Fig. 8 Correlation of total area of grain boundary carbides and fraction of grain boundary M6C carbides with tensile strength.� Fig. 5 Typical